Fuel burning fireplaces and stoves are very popular and desirable in houses and apartments, both for heating as well as for aesthetics. There are two primary types of fuel burning fireplaces and stoves -- those in which solid fuels such as wood, coal, coke, peat or combinations thereof are burned, and those which burn gas and have simulated solid fuel elements, such as artificial logs, to add an element of realism. Gas-fires in stoves and fireplaces have the advantage that they do not require manual refueling or clearing of ashes and they are very controllable. Because of the advantages of gas-fires, considerable efforts have been made to recreate the appearance of traditional solid fuel fires.
Simulated solid fuel gas-fires for fire-places, that is, those having artificial solid fuel elements such as logs, are known. In general, these consist of a simulated fuel bed which is heated to incandescence by flames, or by the product of combustion of flames, to simulate the visible glowing embers of a solid fuel fire. A principle feature in the aesthetic appeal of real, or traditional, solid fuel fires is the existence of visually perceptible, luminous flames flickering about the main fuel bed. Such flames can be closely mimicked in simulated solid fuel gas-fires by burning neat gas, i.e., gas with little or no primary aeration, which produces a yellow flame. Simulated solid fuel gas-fires which incorporate this feature in combination with an incandescent or glowing bed are known. Such neat gas flames, like those produced in real or traditional solid fuel fires, are not static or spatially fixed, but move or waver about irregularly or randomly due to the air flow in the fireplace.
U S. Pat. No. 4,602,609, discloses a simulated solid fuel fireplace having a main heater burner and a plurality of flame effect burners. The flame effect burners burn neat gas (non-aerated) to produce yellow flames, while the heater burner burns a gas-air mixture with a higher air content to produce very hot "blue" flames for space heating purposes. U.S. Pat. No. 4,573,446 also discloses a simulated solid fuel fire which has a neat gas burner for producing visible yellow flames and a main burner for producing blue heat flames.
One drawback common to various known assemblies of this type is the generally incomplete combustion of the neat gas burned in neat gas burners due to the low air-to-gas ratio in the burners. As a result of the incomplete combustion, carbon monoxide and soot are produced as by-products of the flames. For safety reasons, it is desirable to minimize the production of carbon monoxide and soot.
The shortcomings in the prior art gas fireplace and stove assemblies were addressed in U.S. Pat. Nos. 4,883,043 and 4,971,030, both issued to the inventors named herein. These prior patents are directed to gas-fired artificial log fireplace and stove assemblies, respectively, which are designed to visually simulate, in a realistic fashion, a fire in either a fireplace or a stove, and which supply substantial heat to the surrounding room environment. The present invention further improves upon the prior art assemblies to provide a very realistic-looking simulated solid fuel fire and provides substantial heat to the surrounding room environment while producing minimal undesirable combustion by-products.